A novel quantum-dot-based solar cell assembly consisting of core-shell Zn-doped CuInS 2 @ZnS (Zn-CIS@ZnS) quantum dots associated with short ZnO (5 mm in length) nanowires was developed and systematically investigated in terms of its nanostructure and optical properties, associated with corresponding solar cell parameters, i.e., V OC , J SC , fill factor (FF). In this investigation, the photoconversion efficiency of the Zn-CIS-based solar cells without the presence of the ZnS shell can be readily tuned by controlling the Zn/Cu ratio. Furthermore, the efficiency was significantly improved upon the deposition of a thin ZnS shell on these Zn-CIS QDs, where a significant enhancement in shortcircuit current density (J SC ) by 88% was observed because the ZnS coating is able to effectively eliminate excited electron recombination and enhance the charge transfer efficiency from Zn-CIS QDs to ZnO nanowires. Power-conversion efficiency as high as 0.71% can be attained, which is improved more than 2-3 times compared with that without ZnS coating. Such a unique nanoarchitecture through coupling with both core-shell QDs and short ZnO nanowires suggests a promising design for a quantum dot-based solar cell with considerably improved power-conversion efficiency.

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ZnGa204 films have been prepared by radio frequency (RF) magnetron sputtering at various total pressure, RF power, and substrate temperatures. Microstructure and crystallographic orientation were characterized by x-ray diffraction. Surface morphologies were observed by scanning electron microscope. In addition, cathodoluminescence (CL) measurement was employed to observe the emission spectra of ZnGa204 films. The influences of various deposition parameters on the properties of grown films were studied. The optimum substrate deposition temperature for luminous characteristics was about 500~ in this investigation. A blue cathodoluminescent emission peaked at 470 nm was observed. Good luminescent properties were observed in the films which exhibit the standard ZnGa204 x-ray diffraction pattern.

We report a novel and facile method to synthesize phase pure, chemically homogeneous, and highly crystalline CuInS 2 , an important element for optoelectronics, optics, and solar energy applications. This ternary semiconductor compound is grown by magnetic Zn doping under high-frequency magnetic induction at ambient conditions. The magnetic doping gives superparamagnetic heating of the resulting nanocrystals via magnetic induction, causing an accelerating growth rate of the doped CuInS 2 under ambient conditions of 2-3 orders of magnitude faster than conventional autoclave synthesis. Shape evolution of the Zn doped CuInS 2 nanocrystals from initially spherical, to pyramidal, cubic, and finally to a bar geometry, was detected as a function of time of exposure to magnetic induction. These newly-synthesized nanocrystals demonstrated considerably improved optical emission properties compared to those prepared via conventional autoclave methods. Nanostructural development of the nanocrystals was well characterized and a mechanism of crystal growth was proposed.